package com.example.tests;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;

import com.thoughtworks.xstream.XStream;

public class GroupDataGenerator {
	
	public static void main(String[] args) throws IOException {
		if (args.length<3)
		{
			System.out.println("Please, specify 3 parameters: <test data amount>, <file>, <format>");
			return;
		}
		int amount = Integer.parseInt(args[0]);
		File file = new File(args[1]);
		String format = args[2];
		
		if (file.exists())
		{
			System.out.println("File " + file+  " exists, please remove it manually");
			return;
		}
		
		List<GroupData> groups = generateRandomGroups(amount);
		if ("csv".equals(format))
		{
			saveGroupsToCsvFile(groups, file);
		}
		else if ("xml".equals(format))
		{
			saveGroupsToXmlFile(groups, file);
		}
		else 
		{
			System.out.println("Unknown file format "+format);
			return;
		}
	}

	private static void saveGroupsToXmlFile(List<GroupData> groups, File file) throws IOException {
		XStream xstream = new XStream();
		xstream.alias("group", GroupData.class);
		String xml = xstream.toXML(groups);
		FileWriter writer = new FileWriter(file);
		writer.write(xml);
		writer.close();		
	}

	private static void saveGroupsToCsvFile(List<GroupData> groups, File file) throws IOException  {
		FileWriter writer = new FileWriter(file);
		for (GroupData group : groups) {
			writer.write(group.getName()+","+group.getHeader()+","+group.getFooter()+ ",!"+"\n");
		}
		writer.close();
	}
	
	public static List<GroupData> loadGroupsFromCsvFile(File file) throws IOException {
		List<GroupData> groups = new ArrayList<GroupData>();
		FileReader reader = new FileReader(file);
		BufferedReader breader = new BufferedReader(reader);
		String line = breader.readLine();
		while (line!=null)
		{
			String[] part=line.split(",");
			GroupData group = new GroupData()
							.withName(part[0])
							.withHeader(part[1])
							.withFooter(part[2]);
			groups.add(group);
			line = breader.readLine();
		}		
		reader.close();
		breader.close();
		return groups;
	}

	public static List<GroupData> loadGroupsFromXmlFile(File file) throws IOException {
		XStream xstream = new XStream();
		xstream.alias("group", GroupData.class);
		return (List<GroupData>)xstream.fromXML(file);
	}

	public static List<GroupData> generateRandomGroups(int amount) {
		List<GroupData> list = new ArrayList<GroupData>();		
		for (int i = 0; i < amount; i++) {
			GroupData group = new GroupData()
				.withName(generateRandomString("name", 3))
				.withHeader(generateRandomString("header", 3))
				.withFooter(generateRandomString("footer", 3));
			list.add(group);
		}
		return list;
	}
	
	public static String generateRandomString(String text, int period){
		Random rnd = new Random();
		if (rnd.nextInt(period) == 0)
			return "";
		else
			return text + rnd.nextInt();
	}

}
